SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dbd999ea83768e96388985b769c7f612eee07cd4f09b26bbb142bf2bcbf22cb5' 
  AND token = 'q/9pQInZQK9oOs8JZfux5L83o8ASSbajZTOUef4VhIA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}